Efficacy of tourniquet ischemia for strength training with low resistance.
To investigate the efficacy of ischemia in strength training with low mechanical stress, tourniquet ischemia was utilized in low-resistance training. Five untrained subjects conducted one-legged isometric knee extension training with one leg ischemic (I-leg) and the other non-ischemic (NI-leg). Repeated isometric contractions for 2 s with 3 s relaxation in between were continued for 3 min and conducted 3 days/week for 4 weeks as training. Training resistance was 40% of maximal voluntary contraction (MVC) of respective leg and tourniquet ischemia was applied during I-leg training. MVC in I-leg after 2 weeks (9% gain) and 4 weeks (26% gain) were significantly higher than pre-training value (p < 0.05). A significant increase in maximal rate of torque development in I-leg was observed after 4 weeks (p < 0.05). On the contrary, there was no significant changes in either of the parameters in NI-leg. As a consequence, the differences between legs for both parameters were significant after 2 and 4 weeks (p < 0.05 or p < 0.01). The substantial gain in strength and maximal rate of torque development in I-leg demonstrated the efficacy of tourniquet ischemia during low-resistance training of short duration, and suggested the importance of neuromuscular and/or metabolic activity, other than high mechanical stress, to the adapting responses to strength training.
Shinohara
M
M
The University of Tokyo, Department of Life Sciences, Meguro, Japan.
Kouzaki
M
M
Yoshihisa
T
T
Fukunaga
T
T
D000328:Adult; D015444:Exercise; D006801:Humans; D007511:Ischemia; D007537:Isometric Contraction; D007866:Leg / Q000098:blood supply*; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology; D013314:Stress, Mechanical; D014111:Tourniquets; D016474:Weight-Bearing